Ten years ago, they probably were, given that there were some players on the team getting arrested, most notably Michael Irvin. Though part of the blame should fall on Barry Switzer, the head coach at the time of Michael Irvin's arrest, as Barry Switzer didn't give the Cowboys enough discipline, unlike his predecessor, Jimmy Johnson.
Now, it's the Cincinnati Bengals. Those people arrested this year alone (5 in the off-season included) should raise some alarms. The most recent incident happened just this past week, when Chris Henry was suspended by the league for 2 games for violating the league's personal conduct and substance abuse policy. I believe this week is the Bengals' bye week, so next Sunday and the following Sunday, he won't suit up. He was benched the last game for "guilt by association" in Odell Thurman's arrest, meaning he will have missed three consecutive games.
EDIT: It appears I have finally stumbled on a nickname to describe the Bengals' recently-rising arrest rate: The Cincinnati Gangles! (someone referred to them as such here.)